Pipe nipple tool

ABSTRACT

A pipe nipple tool that clamps the nipple wall at one end over its threaded area between an inside mandrel and outside contractable segmented clamping jaws that circumferentially engage the nipple at the roots of its thread with both the mandrel and clamping jaws interlocked to turn as a unit either to tighten or loosen a threaded joint involving the other end of the nipple.

[ Dec. 11, 1973 PIPE NIPPLE TOOL [76] Inventor: Joseph M. Hemingway,14932 Avalon, Dolton, lll. 60419 Apr. 4, 1972 Primary Examiner-James L.Jones, Jr. Assistant Examiner-Mark S. Bicks [22] Filed:

Attorney-Watson D. Harbaugh et al.

211 Appl. No.: 240,982

e CS P m Th se a h t m e .m 70. RNA em 4W9 1 H 5 3 H2 In 32. Q 9Am 9m 8m n UM 2 m C 5L Um ll 21 55 [l end over its threaded area between aninside mandrel and outside contractable segmented clamping jaws thatcircumferentially engage the nipple at the roots of its thread with boththe mandrel and clamping jaws interlocked to turn as a unit either totighten or loosen a threaded joint involving the other end of thenipple.

915,184 Keirn 81/532 14 Claims, 5 Drawing Figures PIPE NIPPLE TOOLBACKGROUND OF THE INVENTION Distortion and pipe damage is a problem inthe pipe fitting trades when installing or removing threaded pipenipples because there is insufficient length and pipe stock,particularly with close or short nipples, to withstand the jaw pressuresof conventional pipe wrenches. Even after the wrench jaws are fingeradjusted tight, they contract further under the 'tuming pressure exertedon the wrench handle and ovate the nipple, damage the threads and renderthe nipple useless whether it is being installed or removed. 1

A standard pipe thread has a 60 thread angle rounded at the crest androot, and, although help can be had in tightening, but not loosening, anipple by a tool that end abuts the nipple when threadedly engaging thethreaded portion of the nipple the resulting forces are essentiallycrosswise to the thread in a way that the upper thread crest may bedistorted and cause a leaking relationship which a pipe thread isdesigned to eliminate. Also, there is a paradox. The tighter the nippleand tool threads become before the parts endabut, the greater theproblem is to remove the tool without again loosening the nipple.Otherwise, anything less than abutment involves only the smallerdiameter thread turns of the thread taper which increases the danger ofthe axial distortion of the thread. 7

Other devices have been tried involving uncontrolled expanding pressuresagainst the inner wall of the nipple before or after tightening isaccomplished. However, splitting the pipe is a hazard which may causeleaking not immediately detected particularly if temperature changes areinvolved with the nipple in use.

SUMMARY 'oF INVENTION In the present invention a tumbler-shaped memberhas its sides externally and internally threaded and then longitudinallysplit into quadrants to provide slightly diverging free ended jawsextending from a heavy end wall. The internal thread has a high'sharpcrest to engage the roots of the nipple thread and the divergence of thejaws is appreciably greater than the taper of the nipple thread so thatthey can'be easily advanced'to cover the length of the nipple thread.The external thread is an easy running thread'preferably with fl'atcrests to receive a runner nut on'them having a mating thread forprogressively contracting the diverging jaws inwardly. The end wall ofthe member is a heavy one having 'a non-circular socket and a centralopening in it. A cooperating member serving as an anvil key closelyfitting the inside wall'of' the nipple is' received in the nipplethrough the central opening andhas a non-circular head non-rotativelymating with the socket in the end wall for simultaneous rotationtherewith.

In operation the jaw member is threaded on the nipple the length of thenipple thread; the anvil key is inserted through the central opening forthe head and socket to mate; the runner nut is moved axially to contractthe jaws and drive the sharp crests into 'tight clamping relationshipwith the roots of the nipple thread even to the point that the ends ofthe'thread segments are under pressure in the roots; and, torque isapplied to the jaw member and anvil key to install or remove the nipplewithout deforming the nippleas more particularly illustrated anddescribed herein.

IN THE DRAWINGS FIG. 1 is a perspective view of an embodimentillustrating the invention;

FIG. 2 is a section taken on line 22 of FIG. 1;

FIG. 3 is a section taken on line 33 of FIG. 2;

FIG. 4 is a cross-sectional view of the wedge key shown in FIG. 2.

FIG. 5 is an enlarged view of the thread relation shown in FIG. 2 withthe runner. nut advanced; and

Referring to FIG. 1 a tool 10 embodying the invention is shown ready forinstallation on one end of a pipe nipple 12 having a standard tapering60 pipe thread 32 and FIG. 5 shows the final relationship of theelements ready for a tightening or loosening of a threaded connection atthe other end of the nipple to a pipe fitting (not shown).

The tool comprises a head portion 16 of substantial thickness having acentral openingl8 outwardly enlarged to provide a shoulder 20 and asquare wrenching socket 22. Inwardly, the opening 18 is enlarged at 24to receive a threaded end 26 of the nipple 12 therein within a segmentedwall 28 defining a taper appreciably greater than the pipe taper. Thewall 28 is internally threaded with a female thread 30 of the same pitchas the pipe thread 32 but whose thread angle preferably is less by 5 to10 degrees to accentuate the sharpness of the crest 33 and provideclearance between the walls of the engaged thread.

The smallest crest diameter of the sharp crest 33 is approximately thesame as the smallest root diameter of the pipe thread root 35 at itsminor taper diameter.

'At their major taper diameters, the crest diameter of the female thread30 is approximately the pitch diameter of the pipe thread 32 so that theinstallationof the tool on the pipe thread is easily accomplished.

The external surface of the tool wall 28 may be provided with a standardcoarse thread, but-preferably is provided with a heavy acme-type thread34 characterized 'by a flat root 36 and flat crest 38 but with a 2 tapercorresponding substantially to the taper of the female thread 30. Bothof the threads 30 and 34 are then segmented by axially extending slotsthrough the tool wall 28. The slots 40 extend inwardly an appreciabledistance'beyond the inner end 42 of the thread and thereby provide axialspring jaws 44 preferably four in number, carrying the thread segmentswhich flex inwardly to a point collectively where the diameters of theexternal thread 34 are uniform throughout its length to receive a runnernut '46 thereon having an internal thread '48 mating with the externalthread on the jaws. When threaded on the segments to a startingpointadjacent the head'l6 the free ends of the jaws resume theirtaperorientation already described.

a nipple having a major production tolerancediameter.

The anvil key 50 has a square head 58 which nonrotatively engages "inthe square socket 22 when the anvil key is fully inserted in placethrough the opening l8.-The head'preferably extends a substantialdistance outwardly to receive a nut and bolt wrench thereon (not shown)which will turn the barrel and anvil key in unison.

The runner nut 46 is then advanced on the external threads 34 to drivethe sharp crests 33 of the internal thread segments 308 against the root35 of the pipe thread 32, and progressively clamping them tighter andtighter to the point of maximum expected wrenching effort. In doing thisthe nut 46 moves on two pairs of co-cylindrical surfaces at 36 and 38quite easily with lubrication at minimal effort. The nipple body 12being supported by the anvil key 50 at surface 56 cannot deform tolocalize the applied effort but withstands all radial and torsionaleffort uniformly throughout its threaded length to attain not only theadvantage of abutment wrenching but also maintain thread form and itssealing characteristics and provide for loosening as well as tighteningoperations.

Although all threads described may turn in the same direction it ispreferred that the runner nut thread be a left hand thread so that therelative manual action of the wrenches in tightening or loosening thenut is in opposite directions of rotation for ease of handling andapplication. This is also an advantage if simultaneous wrenchingengagement of both the runner nut 46 and head portion 16 occurs, evenunintentionally, because there would be no loosening of the tool whileendeavoring to loosen the nipple.

On the other hand, since a nipple can be adequately tightened bywrenching the square head 58 of the tool without slack take-up betweenhead portions 16 and 58 there is no disadvantage when tightening anipple, but rather an advantage with the left hand thread being able toloosen the runner nut 46 in the nipple tightening direction to removethe tool with or without holding the wedge key, and, if the anvil key 50is wrench held the tool loosening directions are again in oppositedirections for manual wrenching conditions without loosening the nipple.Accordingly, the nipple and the tool are easily useable in closequarters, where nipples usually are disposed, without any need fortouching the nipple with a deforming wrench.

Preferably, the runner nut 46 and head portion 16 are approximately thesame size so that either or both can be held by the same wrench whilethe square head of the wedge key is of a different size so that twoidentical wrenches need not be required to use the invention since mostjoumeymen have a range of wrench sizes rather than duplicates.

As already noted an important object of the invention is in not touchingthe nipple body with a distorting wrench. The nipple is pressurecontacted at the root of its thread where thread make-up and sealing isnot damaged and the contact does not extend continuously more than aquarter turn of the thread with a quadrant segmentation of the thread.Furthermore, the clamping action is in a radial direction through thewall of the nipple without any displacement of metal so that the nippleis not contacted in any way which would damage a thread seal or weakenthe nipple wall.

Where a nipple is to be removed whose thread is rusty and inner walllined with scale, the inner end of the anvil key is sharply square todislodge internal scale for metal to metal contact as it is moved intoposition, and the sharp crests of the tool thread segments bite throughrust to the metal at the roots of the pipe thread and still providesroom for displaced material between the sides of the meshing threads.Thereby the segmented ends of the sharp thread segments can takepurchase in nipple metal at the roots of the nipple thread as a seriesof teeth peripherally embedding in the metal uniformly and peripherallyto exert rotation in either direction without any axial effort on thenipple threads at either end.

Although the stress bearing parts may be made of cast steel, the partsare preferably made of easily machinable steel, hardened for use, andall are completely separable for ease of cleaning and inspection as wellas usable with conventional tools that are present in a journeymans toolbag.

What is claimed is:

l. A tool for rotating a pipe nipple comprising a central member havinga head element and circumferentially spaced wall segments extendingaxially therefrom defining jaws,

thread means on the inner faces of said jaws defining segmented sectionsof a sharp crest thread having a standard pipe thread pitch and a threadangle appreciably less than that of a standard pipe,

means engaging the outer surface of said jaws for contracting them underpressure to clamp the sharp crest sections against the roots of astandard pipe tapered thread, and

means for rotating said central member about the axis of said threads.

2. The combination called for in claim 1 in which said engaging meanscomprises a clamping thread defined on the outer surface of saidsegmented sides, and

a runner nut threaded on said clamping thread to vary the effectivecrest diameter of said sharp crest thread.

3. The combination called for in claim 1 including an anvil key elementreceived through said head to closely fit and engage the inside surfaceof a nipple within said aws.

4. The combination called for in claim 3 in which the head element andanvil key element have interfitted elements to secure said elementsagainst relative rotation.

5. The combination called for in claim 4 in which one of said elementshas a wrench engageable shape for rotating said elements simultaneously.

6. The combination of claim 2 in which the clamping thread turns in adirection opposite to that of said thread means.

7. The combination of claim 2 in which said sharp crest thread has 1. agreater height than that of said pipe thread when clamped in place,

2. a pitch diameter appreciably greater than that of the pipe thread toprovide clearance between its sides and a standard pipe threadengageable therewith; and

3. a minor crest diameter that is less than that of said pipe threadroot diameter for an interference clamping relationship therewith.

8. The process of threadably tightening and loosening a standard pipenipple comprising,

engaging only the root of the nipple thread circumferentially over aplurality of thread turns with portions of a sharp crest mating threadedge,

applying a contracting clamping pressure upon the root of the nipplethread,

rigidly supporting the inner wall of the nipple by a member over asubstantially peripheral area of engagement within the confines of thearea of said clamping pressure, and

rotating said member and thread edge portions simultaneously about theaxis of said nipple thread to threadably tighten and loosen a standardpipe nipple.

9. The steps called for in claim 8 in which said thread edge portionsare thread segments having square ends defining sharp corners engagingin the metal at the root of said nipple thread.

10. The steps called for in claim 8 in which the root is rounded and thethread angle of the standard thread is 60 and the thread angle of thesharp crest mating thread is appreciably less than 60 for the threads toclear at their pitch diameters.

11. A tool for clamping and rotating a pipe nipple comprising atumbler-shaped member having an end wall and its sides externally andinternally threaded and longitudinally split into quadrants that provideslightly diverging free-ended jaws extending from the end wall, saidinternal thread having a high sharp crest to engage the roots of astandard pipe thread with a divergence taper appreciably greater thanthat of a pipe thread, said external thread having a flat crest and aflat root,

a runner nut mounted on said member adjacent to said end wall and havinga mating thread engaging the external thread for movement from said endwall to progressively contract the diverging jaws inwardly as it isrotatively tightened,

said end wall of said member being a heavy one having an externalopening and a non-circular socket in it, and

an anvil key received through said external opening with its wall inpredetermined radially spaced relation from said internal thread andhaving a noncircular and mating non-rotatively with said socket in theend wall for simultaneous rotation therewith.

12. A tumbler-shaped member having a heavy end wall with a noncircularsocket and a central opening through it and longitudinally segmentedslightly diverging free-ended jaws having internal and external threads,

said internal thread having high sharp crest edges to engage the rootsof a standard pipe thread with the divergence of the jaws appreciablygreater than the taper of a standard pipe thread so that they can beeasily advanced to cover the length of a standard pipe thread and theexternal thread being an easy running thread,

running nut means on said external thread for progressively driving thediverging jaws inwardly under a contractive force as it is advancedtowards the free ends of the jaws to drive said sharp edges intometal-to-metal engagement under pressure with the root of a standardpipe thread, and

a headed anvil key means for closely fitting the inside wall of a pipehaving said standard pipe thread externally thereon and receivablethrough the central opening with a non-circular head non-rotativelymating with said socket in the end wall for simultaneous rotationtherewith.

13. The combination called for in claim 12 in which said externalrunning thread mates with the thread of the running nut means and boththreads have mating flat roots and crests for transmitting saidcontractive force essentially in a directly radial direction between thethreads.

14. The combination called for in claim 12 in which said anvil key has atightening taper and longitudinal roughening whose major diameter sizeis large enough for them to engage the inner surface of a known pipesize with contact pressure when inserted with such a pipe having a majorproduction tolerance diameter.

1. A tool for rotating a pipe nipple comprising a central member havinga head element and circumferentially spaced wall segments extendingaxially therefrom defining jaws, thread means on the inner faces of saidjaws defining segmented sections of a sharp crest thread having astandard pipe thread pitch and a thread angle appreciably less than thatof a standard pipe, means engaging the outer surface of said jaws forcontracting them under pressure to clamp the sharp crest sectionsagainst the roots of a standard pipe tapered thread, and means forrotating said central member about the axis of said threads.
 2. a pitchdiameter appreciably greater than that of the pipe thread to provideclearance between its sides and a standard pipe thread engageabletherewith; and
 2. The combination called for in claim 1 in which saidengaging means comprises a clamping thread defined on the outer surfaceof said segmented sides, and a runner nut threaded on said clampingthread to vary the effective crest diameter of said sharp crest thread.3. The combination called for in claim 1 including an anvil key elementreceived through said head to closely fit and engage the inside surfaceof a nipple within said jaws.
 3. a minor crest diameter that is lessthan that of said pipe thread root diameter for an interference clampingrelationship therewith.
 4. The combination called for in claim 3 inwhich the head element and anvil key element have interfitted elementsto secure said elements against relative rotation.
 5. The combinationcalled for in claim 4 in which one of said elements has a wrenchengageable shape for rotating said elements simultaneously.
 6. Thecombination of claim 2 in which the clamping thread turns in a directionopposite to that of said thread means.
 7. The combination of claim 2 inwhich said sharp crest thread has
 8. The process of threadablytightening and loosening a standard pipe nipple comprising, engagingonly the root of the nipple thread circumferentially over a plurality ofthread turns with portions of a sharp crest mating thread edge, applyinga contracting clamping pressure upon the root of the nipple thread,rigidly supporting the inner wall of the nipple by a member over asubstantially peripheral area of engagement within the confines of thearea of said clamping pressure, and rotating said member and thread edgeportions simultaneously about the axis of said nipple thread tothreadably tighten and loosen a standard pipe nipple.
 9. The stepscalled for in claim 8 in which said thread edge portions are threadsegments having square ends defining sharp corners engaging in the metalat the root of said nipple thread.
 10. The steps called for in claim 8in which the root is rounded and the thread angle of the standard threadis 60* and the thread angle of the sharp crest mating thread isappreciably less than 60* for the threads to clear at their pitchdiameters.
 11. A tool for clamping and rotating a pipe nipple comprisinga tumbler-shaped member having an end wall and its sides externally andinternally threaded and longitudinally split into quadrants that provideslightly diverging free-ended jaws extending from the end wall, saidinternal thread having a high sharp crest to engage the roots of astandard pipe thread with a divergence taper appreciably greater thanthat of a pipe thread, said external thread having a flat crest and aflat root, a runner nut mounted on said member adjacent to said end walland having a mating thread engaging the external thread for movementfrom said end wall to progressively contract the diverging jaws inwardlyas it is rotatively tightened, said end wall of said member being aheavy one having an external opening and a non-circular socket in it,and an anvil key received through said external opening with its wall inpredetermined radially spaced relation from said internal thread andhaving a non-circular and mating non-rotatively with said socket in theend wall for simultaneous rotation therewith.
 12. A tumbler-shapedmember having a heavy end wall with a noncircular socket and a centralopening through it and longitudinally segmented slightly divergingfree-ended jaws having internal and external threads, said internalthread having high sharp crest edges to engage the roots of a standardpipe thread with the divergence of the jaws appreciably greater than thetaper of a standard pipe thread so that they can be easily advanced tocover the length of a standard pipe thread and the external thread beingan easy running thread, running nut means on said external thread forprogressively driving the diverging jaws inwardly under a contractiveforce as it is advanced towards the free ends of the jaws to drive saidsharp edges into metal-to-metal engagement under pressure with the rootof a standard pipe thread, and a headed anvil key means for closelyfitting the inside wall of a pipe having said standard pipe threadexternally thereon and receivable through the central opening with anon-circular head non-rotatively mating with said socket in the end wallfor simultaneous rotation therewith.
 13. The combination called for inclaim 12 in which said external running thread mates with the thread ofthe running nut means and both threads have mating flat roots and crestsfor transmitting said contractive force essentially in a directly radialdirection between the threads.
 14. The combination called for in claim12 in which said anvil key has a tightening taper and longitudinalroughening whose major diameter size is large enough for them to engagethe inner surface of a known pipe size with contact pressure wheninserted with such a pipe having a major production tolerance diameter.